21 answers
Another (no coding) option that I'll just throw out there:
In the User Interface Settings if you enable "Enable Related List Hover Links" it will place a link at the Top of the Lead detail page for each related list. If you mouse-over the Open Activity or Activity History links at the top of the Lead record it will display the:
[New Task] [New Event] [New Meeting Request]
or
[Log a Call] [Mail Merge] [Send an Email] [Reply]
buttons at the top of the page